"I'm really, really excited!" Pizzolo said during a phone call filled with laughter. "Sydney is so amazing, and it's going to be big shoes to fill."

Pizzolo and Lucas shared a dressing room at the Circle in the Square Theatre, which they decorated with their own artwork. Pizzolo said she will miss Lucas, explaining, "Sydney was always making up cool ideas. She was witty and kind and always had new adventures."

Pizzolo is no stranger to the character of Small Alison, having understudied Lucas as well as co-stars Oscar Williams and Zell Steele Morrow, who play Alison's brothers, John and Christian. She has gone on for Alison several times already, and she described the first time "playing airplane" with Michael Cerveris, who plays Alison's father, as "an incredible fly."

Read more about Pizzollo's life as an undestudy here.

Pizzolo came to Fun Home after playing the title role in Matilda the Musical, in which she shared the role with three other girls. Playing Alison will mark her first time performing full-time, eight shows a week, on Broadway. But she's not worried about staying healthy with her new schedule; instead, she thinks performing in a show she admires so much will be "energizing." "I think it’s an honor and privilege to get to do a show that’s a real story by Alison Bechdel about her family," she said. "Jeanine [Tesori] and Lisa [Kron] and Sam [Gold] are so great. They have so much talent. I’m going to try to do my best for them. The first time I ever saw the show it touched my heart. I thought, 'Wow, this musical’s amazing.'"

She's also excited to share the stage with her young co-stars, Williams and Morrow, with whom she performs the song "Come to the Fun Home," advertising the family funeral home.

"It's my favorite part of the show!" she said giggling. "Working with Oscar and Zell is amazing." She recalled her audition, during which she also sang the song, saying, "I thought, 'This is totally Jackson Five. If I ever get to do this, I'll probably think about this song all the time... Let's dance!'"

If she had known at her audition that she would be the understudy, and then go on full time as Small Alison, what would Pizzolo say to herself?

"Just to be ready. And have as much fun as you can have."

And, she said, she is ready to go on full-time Oct. 6: "Being in that part is going to be really crazy awesome."